There are many medical treatments and diagnostic procedures the efficacy of which can be improved by coordinating such treatment or procedure with a patient""s breathing cycle. In many instances the patient can control their breathing to assist the medical provider. However, some patients are not able to control their breathing, for example patients on ventilators. Accordingly, an apparatus which could facilitate the timing of such a medical treatment or a diagnostic procedure with respect to a patient""s breathing cycle would be beneficial to the patient.
As an example, chest x-rays are often taken in the intensive care unit using portable x-ray machines. These x-ray images provide important information to the clinician and, therefore, the quality of the images is important. Factors which can affect the quality of chest x-rays include: patient position and movement; ability of patient to receive and respond to instruction; penetration of the x-ray beam; and, perhaps most important, timing of the x-ray with patient insufflation.
Typically, the highest quality chest x-ray images are attained when the x-ray is taken at peak insufflation because there is less tissue mass per unit area, and penetration is uniform. Accordingly, patients who are able to receive and respond to instruction can be instructed to take and hold a deep breath long enough to take the required x-rays. However, for patients on a ventilator, in order to take the x-ray at peak insufflation, the person taking the x-ray must attempt to accurately time the x-ray with the cycle of the ventilator. When the x-ray is not timed correctly, it may be less than optimal and additional costs are incurred if it is necessary to retake the x-rays. Furthermore if time is critical, the care giver may be forced to provide care with inadequate information.
Accordingly, there exists a need in the art for a method and device which can ensure that chest images of patients on ventilators are taken at a desired degree of insufflation to enhance the quality of such chest images. In particular, a device which could interface a ventilator with an x-ray machine to ensure chest x-rays are taken at peak ventilation would improve the quality of such chest x-rays and, therefore, improve the quality of care for ventilated patients.
Additional situations where the efficacy of the medical treatment or procedure can be affected by timing the treatment or procedure with respect to a desired point in the breathing cycle include, but are not limited to, inhalation therapy, oxygen (O2) delivery, blood pressure measurements, and pulse oximeter optoplethysmograms. With inhalation therapy and O2 delivery, timing the delivery of the appropriate substances with respect to the breathing cycle can affect the dose administered, the amount of waste, and costs. With blood pressure measurements and pulse oximeter optoplethysmograms, the timing of the measurements with respect to the breathing cycle can affect, for example, the accuracy of the readings.
Accordingly, there exists a need in the art for a method and device which can trigger an event with respect to a patient""s breathing cycle.
The subject invention pertains to a method and apparatus for triggering an event with respect to a patient""s breathing cycle. The subject invention is applicable to human or animal patients. In a specific embodiment, the subject invention pertains to a novel method of coordinating a chest x-ray with the ventilatory cycle. The methods and apparatus of the subject invention are particularly advantageous for use in chest radiography. In a specific example, the subject invention concerns a novel device for interfacing a ventilator and an x-ray machine to ensure that an x-ray chest image can be taken at a desired degree of ventilation of the patient, for example, peak inspiration. The interfacing of a ventilator and an x-ray machine, according to the subject invention improves the chest image quality and, therefore, improves the quality of medical care received by the patient. In a preferred embodiment, the taking of an x-ray can be accomplished by emulating an x-ray machine firing handle with software, for example, on a notebook personal computer.
Further embodiments of the subject invention pertain to, for example, the delivery of inhalants, delivery of oxygen (O2), blood pressure measurements, and pulse oximeter optoplethysgrams. With respect to the delivery of inhalants and the delivery of O2, the method and apparatus of the subject invention can improve the efficiency of the delivery of the appropriate substance, improve the accuracy of administering the correct dose, and reduce waste and costs. With respect to blood pressure measurements and pulse oximeter optoplethysgrams, the method and apparatus of the subject invention can improve the clarity of the film increasing the accuracy of the films"" interpretation by timing the measurements with respect to the breathing cycle of a patient.